RGD uses the Human Disease Ontology (DO, https://disease-ontology.org/) for disease curation across species. RGD automatically downloads each new release of the ontology on a monthly basis. Some additional terms which are required for RGD's curation purposes but are not currently covered in the official version of DO have been added. As corresponding terms are added to DO, these custom terms are retired and the DO terms substituted in existing annotations and subsequently used for curation.
A lymphatic system disease characterized by he presence of intestinal lymphangiectasia, mental retardation, and characteristic facial anomalies. It is inherited in an autosomal recessive pattern. Most individuals with Hennekam syndrome have characteristic facial abnormalities, such as a flat face with accompanying puffy eyelids and hypertelorism; the nasal bridge is typically flat and the ears are typically small. Congenital extremity and genital lymphedema is present in most patients. (DO)